Move include/rebar.hrl to src/rebar.hrl

rebar.hrl is only meant to be used by src/*.
Fix a format of a debug output
Fix spec file look up

When trying to skip spec files under deps/ directory,
ignore "deps" component which is also included in Cwd.
For example, "/home/deps/src/myapp/test/cover.spec"
contains "deps" component but should not be skipped if
Cwd is "/home/deps/src/myapp/".
fix double "the" in a comment

noted by @tuncer
use the effective deps dir instead of hardcoding "deps"

suggested by @tuncer
Merge pull request #130 from yamt/ct-fixes

ct fixes
Merge pull request #281 from tuncer/rebar-h-internal

Move include/rebar.hrl to src/rebar.hrl
Revert "Merge pull request #171 from fenollp/using-stdlib"

This reverts commit 3297ffec2c89c6b7135165b4bfaeaeb07167c33c, reversing
changes made to 0401debb3cf23d67affbe465a7a438049180a608.