Bump version number to 3.0.0-SNAPSHOT.

Once we bump the version, I can branch for release/3.0.x.

I removed some versioned dependencies between our own core plugins (sdt.debug
to sdt.core, sdt.spy to sdt.core), as I think they are not needed and are just
a pain to maintain.
Adds anon function and flags in cache

Creates an new map cache to store information about method containing the code
of anonymous functions, and method flags.
With tests.

Fixes #1001001
Merge pull request #295 from dragos/set-versions

Bump version number to 3.0.0-SNAPSHOT.
Merge pull request #296 from skyluc/issue/debugger-cached-method-flags-1001001

Adds anon function and flags in cache
Debugger code does not handle checked exceptions in many places

I've added a number of FIXMEs notes in the debugger codebase where checked
exceptions are not handled.

Furthermore, I've added a couple of comments that should help better understanding
some of the assumptions we have in the debugger module (this is related to the discussions
that happened in the [PR #219](https://github.com/scala-ide/scala-ide/pull/219))

Re #1001487
Merge pull request #294 from dotta/issue/unhandled-checked-exceptions-1001487

Debugger code does not handle checked exceptions in many places
Rebuild Scala projects after a global compiler settings change.

If the user changes compiler settings on the Scala Preferences page, all Scala
projects that 'inherit' these settings should be rebuild. The existing logic
was dealing only with the case where *project-specific* settings were changed.

Fixed #1001460.