Fix build and split macros and plugin.

[jeff-davis]

No description provided.

[stereobooster]

current master

rustc --version
rustc 1.12.0-nightly (5e18b4bad 2016-07-08)
(3ff8369) cargo build
   Compiling postgres_extension v0.0.1 (postgres-extension.rs)
src/lib.rs:11:1: 11:30 warning: type `fmNodePtr` should have a camel case name such as `Fmnodeptr`, #[warn(non_camel_case_types)] on by default
src/lib.rs:11 type fmNodePtr = *mut c_void;
              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/lib.rs:12:1: 12:32 warning: type `fmAggrefPtr` should have a camel case name such as `Fmaggrefptr`, #[warn(non_camel_case_types)] on by default
src/lib.rs:12 type fmAggrefPtr = *mut c_void;
              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/lib.rs:73:14: 73:20 warning: private trait in public interface (error E0445), #[warn(private_in_public)] on by default
src/lib.rs:73     where T: PgType {
                           ^~~~~~
src/lib.rs:73:14: 73:20 warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
src/lib.rs:73:14: 73:20 note: for more information, see the explanation for E0446 (`--explain E0446`)
src/lib.rs:461:5: 461:35 warning: struct field is never used: `ptr`, #[warn(dead_code)] on by default
src/lib.rs:461     ptr: *mut FunctionCallInfoData,
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/lib.rs:469:5: 469:15 warning: struct field is never used: `val`, #[warn(dead_code)] on by default
src/lib.rs:469     val: usize
                   ^~~~~~~~~~
src/lib.rs:473:20: 473:25 warning: unused variable: `value`, #[warn(unused_variables)] on by default
src/lib.rs:473     pub fn new_str(value: &str) -> Datum {
                                  ^~~~~

vs this branch

rustc --version
rustc 1.12.0-nightly (5e18b4bad 2016-07-08)
(5b36517) cargo build
   Compiling postgres_extension v0.0.1 (postgres-extension.rs)
rustc --version
rustc 1.10.0 (cfcb716cf 2016-07-03)
(5b36517) cargo build
   Compiling libc v0.2.13
   Compiling postgres_extension v0.0.1 (postgres-extension.rs)