uhd:  include gnuradio paths for swig build first

This fixes a potential issue where swig sees old installed headers,
where it should be seeing in-tree headers.
filter: removing '.version' lines in ASM code for compat with CLANG.
core: Adding a file sink block that stores metadata with file.

Current working version only has a single header at the top of the file.

Must update to add metadata fields when changes occur. Also adding extra_header structure to store extram, users-specified info.
core: adding Python files to easily parse header info of a file.

Also a utility script that you pass a filename to and it prints out the meta data.
core: adding GRC file for file metadata sink
core: Update file_meta_sink to inject headers into data stream.

When a tag with updated metadata information is received, close out the previous header (by setting the segment size) and create a new header with the new data. Specifically for sample rate and time stamps. Will be useful for extra_dict when implemented.
core: adding ability to handle extra data in headers.
swig: tweaks for swig makedepend

* only search %include/import in .i files
* when in regular headers use #include
* stop adding all inc paths when file found
core: moving Boost_INCLUDE_DIRS to be last
Merge branch 'maint'
Merge branch 'master' into next
Merge branch 'next' of gnuradio.org:gnuradio into next
ctrlport: forgot a check in the Python dirs for controlport.
docs: Removing some obsoleted Doxygen commands per issue #498.

These were set to the defaults and so should not affect previous versions of Doxygen.
Merge branch 'master' into next
core: adding a max segment size to metadata files.

Automatically generates a new header after the MSS is reached.

Also adds a metadata format version number (starting at 0).
core: updated metadata structure to use relative header info.

Now the start tag info in the header is relative to the begining of the header (so, basically, the size of the header + extras).
core: Update metadata file sink to better handle tags in the right spot.
core: metadata file parser updated for more sig figs on display.
core: Use sample and relative rate to update header based on num samples.

When the max segment size is reached, we insert a new header. This updates the timestamp on that header based on the number of samples seen.