Loudness analyzer updates, added actions, misc stuff...

Sorry for such a massive pull request, things just got added while working on loudness analyzer :)

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#### Analyze and normalize loudness:
##### Analyze loudness dialog:
 - Analyzer can now measure true peak (disabled by default since it prolongs analysis due to resampling - see Options to enable/disable)
  - Double-click true peak cell to move edit cursor to true peak location (or right-click selected item/track in list view to reveal the option)
 - Added user preference to display either LUFS or LU (see Options->Unit).
   - To set reference level for 0 LU and formatting of LU unit, see Options->Global preferences (or run SWS/BR: Global loudness preferences)
   - Right-click menu entry for normalizing follows Options->Unit and will alternate between "Normalize to -23 LUFS" and "Normalize to 0 LU"
  - Normalizing to specific value can normalize to both LUFS and LU
 - Export list of analyzed items/tracks to clipboard or file
  - To export the list, select items in list view, right-click them and select "Export formated list to clipboard/file"
  - For setting the format of exported items, see Options->Export format
   - Formating supports wildcards. Wildcards description can be found in the same dialog. To hide description, simply resize the dialog
   - Besides typing, wildcards can also be inserted using the "Wildcard" button.
   - Previously used format patterns are stored in the "Wildcard" button submenu
 - Other:
  - Right-click menu entry for creating loudness graph no longer queries range, instead it uses range set in Options->Global preferences (or SWS/BR: Global loudness preferences)
  - Normalize dialog is no longer modal (but will be closed if loudness analyzer is closed/hidden to avoid confusion)
  - Display new items/tracks in list view as soon as they're analyzed
  - Analyze button changes caption depending on what is to be analyzed
  - Added Help... menu entry to options menus
   - Note: opens http://wiki.cockos.com/wiki/index.php/Measure_and_normalize_loudness_with_SWS|wiki page on everything loudness related in SWS| which is currently unfinished (if you want to contribute you're more than welcome)
  - Various small fixes

##### Added actions:
 +SWS/BR: Global loudness preferences...
  - Note: Preferences set here affect everything loudness related in SWS (analyze loudness dialog and separate normalize actions)
   - 0 LU reference can be set to an arbitrary value (most common values are provided in the dropdown)
   - LU unit format only affects display of LU unit in various dialogs
   - Envelope graph range affects drawing range when drawing loudness envelopes in Analyze loudness dialog
 +SWS/BR: Normalize loudness of selected items to 0 LU
 +SWS/BR: Normalize loudness of selected tracks to 0 LU

##### Other:
 - Renamed SWS/BR: Normalize loudness of selected items to SWS/BR: Normalize loudness of selected items/tracks (also no longer modal)
 - Removed SWS/BR: Normalize loudness of selected tracks

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#### Added actions
##### Main:
 - SWS/BR: Select envelope points on/between grid (2 versions: time selection and normal)
 - SWS/BR: Add envelope points located on/between grid to existing selection (2 versions: time selection and normal)
 - SWS/BR: Delete envelope points on/between grid (2 versions: time selection and normal)
 - SWS/BR: Create project marker at mouse cursor
 - SWS/BR: Create project marker at mouse cursor (obey snapping)
 - SWS/BR: Insert 2 envelope points at time selection to all visible track envelopes
 - SWS/BR: Insert 2 envelope points at time selection to all visible track envelopes in selected tracks
 - SWS/BR: Show all active FX envelopes for selected tracks
 - SWS/BR: Show all FX envelopes for selected tracks
 - SWS/BR: Show all/volume/pan/mute active send envelopes for selected track
 - SWS/BR: Show all/volume/pan/mute send envelopes for selected track
  - Note: all show FX/send envelope actions come in 3 flavors : show, hide and toggle show
 - SWS/BR: Show/hide track envelope for last adjusted send (3 verions)
  - Note: that's right, due to API limitation it's last adjusted, not touched
 - SWS/BR: Enable "Ignore project tempo" for selected MIDI items preserving time position of MIDI events (use tempo at item's start)
  - Note: the action is meant for http://forum.cockos.com/showthread.php?p=1374175#post1374175|these kind of issues|

##### MIDI editor:
 - SWS/BR: Save/Restore selected events in last clicked CC lane (8 slots) (Restore has 2 versions: last clicked lane or all visible lanes)
 - SWS/BR: Insert CC event at edit cursor in CC lane under mouse cursor (active item only)

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#### ReaScript
##### Other:
 - Changed envelope object type in BR_EnvAlloc and other functions to avoid confusion (existing scripts should be unaffected)

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#### Fixes
+ Improved deleting tempo markers with different time signatures when using SWS/BR: Delete tempo marker and preserve position and length of items (including MIDI events)
+ Preserve options between REAPER sessions set with these actions:
 - SWS/BR: Set "Apply trim when adding volume/pan envelope"
 - SWS/BR: Toggle "Playback position follows project timebase when changing tempo"

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#### Other
+ Increased all SWS/BR slot actions to 8 slots
+ Display proper dialog icon (same one REAPER uses) in all dialogs (win only)
+ Added tempo actions to Main menu > Extensions > Tempo