Create epub versions of tutorial and ref manual.

Pandoc can create epub verions of the markdown files. Since the docs
are lengthy, epubs are handy to have around. Two rules to create epub
versions of the reference manual and the main tutorial are added here.

Signed-off-by: Noufal Ibrahim <noufal@nibrahim.net.in>
tagging issue number(#10381)
disable tests on android since tcp/ip permission cannot be acquired without help of apk
temporarily disable tests on android and tagging issue number #10378
temporarily disable tests on android and tagging issue number #10379
temporarily disable tests on android and tagging issue number #10380
temporarily disable tests on android and tagging issue number #10393
Remove a debug! statement before I/O is ready

The logging macros all use libuv-based I/O, and there was one stray debug
statement in task::spawn which was executing before the I/O context was ready.
Remove it and add a test to make sure that we can continue to debug this sort of
code.

Closes #10405
auto merge of #10226 : nibrahim/rust/docepub, r=alexcrichton

Added two new rules to create epubs out of the tutorial and reference manual source files. This is useful and doesn't add any new dependencies to the build process.
auto merge of #10406 : alexcrichton/rust/issue-10405, r=huonw

The logging macros all use libuv-based I/O, and there was one stray debug
statement in task::spawn which was executing before the I/O context was ready.
Remove it and add a test to make sure that we can continue to debug this sort of
code.

Closes #10405
Register new snapshots
Enable uv pipe tests on windows

Turns out the pipe names must have special names on windows. Once we have
special names, all the tests pass just fine.

Closes #10386
auto merge of #10408 : alexcrichton/rust/snapshots, r=huonw

Mostly just using the `system` abi where possible.
Clean lint on test build
vec: with_capacity: check for overflow

Fixes #10271
Implement `size_hint` for Range

Closes #8606
auto merge of #10416 : cmr/rust/range_size_hint, r=huonw
doc: Don't mention TLS in condition tutorial
auto merge of #10394 : yichoi/rust/make_check_pass_android, r=brson

To enable test on android bot #9120

some tests are disabled and can be fixed further.
auto merge of #10409 : alexcrichton/rust/issue-10386, r=brson

Turns out the pipe names must have special names on windows. Once we have
special names, all the tests pass just fine.

Closes #10386